The present invention is related to large, up to 500 kiloton, forging presses and more particularly to a built-in lifting and manipulating structure which is permanently installed in the foundation pit of the forging press to reduce the down time of certain press maintenance operations.
The present invention is closely related to the subject matter described in patent application Ser. No. 821,790 entitled "A FORGING PRESS WITH ADJUSTABLE DAYLIGHT AND WITH YOKE DESIGN FOR ATTACHING TIE-RODS TO CROSSHEADS" which is commonly assigned with the present application. The subject matter thereof is incorporated herein by reference.
Forging presses are used for shaping metallic workpieces into end products of desired shape by pressing said pieces between a pair of dies to give them an intended shape.
Forging presses are large structures, equivalent to a multistory building, and it is common to house a portion of the forging press in a foundation pit below ground.
As described, for example in the aforementioned patent application, one of the major structures of the forging press is its frame which includes a horizontally extending lower crosshead assembly extending generally parallel to the floor of a main chamber in the foundation pit and a pair of vertical columns, often referred to as tie-rods, connected to opposite ends of the lower crosshead assembly and, at their other ends to an upper crosshead assembly located above ground level. The massive size of such a frame and its weight which easily exceeds many hundreds, or even thousands, of tons, pose a difficult problem whenever the frame components must be disassembled for either maintenance, repair or adjustments. It is not unusual that a disassembly of even a portion of the frame requires an entire week and sometimes several weeks and results in a very costly loss of forging press availability.